


Thunder In Your Heart

by Myrime



Category: Marvel, Marvel Cinematic Universe, The Avengers (Marvel) - All Media Types
Genre: 2012 avengers, Angst, Don't copy to another site, Friendship, Hurt/Comfort, M/M, Magic, Power Swap, Pre-Relationship, Protective Hulk (Marvel), Protective Thor (Marvel), Self-Acceptance, Team Bonding, wise thor
Language: English
Status: Completed
Published: 2019-08-21
Updated: 2019-08-21
Packaged: 2020-09-23 12:11:14
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,775
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20339911
Author URL: https://archiveofourown.org/users/Myrime/pseuds/Myrime
Summary: It would have been too easy if the spell only made Thor an expert on nuclear phsyics and Bruce able to swing Mjolnir. Instead, Thor is turning green, battling with the Hulk stuck in his body, and Bruce cannot touch anyone without shocking them with the electricity flying from his fingertips.Meanwhile, New York is living through the longest thunderstorm in recorded history. Nothing is ever simple where the Avengers are concerned.





	Thunder In Your Heart

**Author's Note:**

> Another entry for the [Iron Man Bingo 2019 Round 2](https://iron-man-bingo.tumblr.com/), square: Power Swap
> 
> Enjoy!

The full extent of the spell does not become immediately obvious, which is a small miracle, considering the instant panic that breaks out when the Hulk goes down with a roar in the blinding light, and Thor crashes to the ground like a marionette with his strings cut.

It all happens so suddenly that no one can tell exactly what happened. They did not even know the guy in the funny hat they were fighting could wield magic until he started attacking them with coloured lightning bolts from his hands and turned nearby stones and objects into animated suits of armour fighting for him. If magic were not one of Tony’s least favourite things in the world, the guy would have gotten bonus points for his imaginative attacks.

Even before the light from the magic explosion has faded, Tony directs a small grenade at the two animated suits of armour he is fighting and launches into the air to check on his friends. Possible danger aside, they just saw two of their strongest fighters go down. Two of their friends. He trusts the rest of the Avengers to take care of the battle so long.

“They’re alive but unconscious,” JARVIS tells him, scanning the debris before Tony has a visual on them.

Tony finds Thor first. Lying on the ground, he looks fragile despite his massive form. Despite JARVIS’ reassurance, he kneels down and, retracting the gauntlet on one hand, checks for a pulse. He finds it immediately, strong and steady, appearing almost angry in its intensity.

“Come on, buddy,” Tony mutters as he reaches out to shake Thor’s shoulders, “wake up.”

There is no reaction. On the first glance, there is no visible wound either. No blood, no broken bones, not even a dent in the armour.

_Just unconscious_, Tony thinks to himself as he studies the vitals JARVIS brings up helpfully in the HUD. That is certainly not good but nothing Tony can do anything about right now. Further answers have to wait until Thor wakes up.

“Keep an eye on him,” Tony says to JARVIS before he turns around and goes looking for the Hulk.

Anyone able to take down the Hulk is a more serious opponent than they first thought. After only a few steps, Tony finds something even more worrying than that.

In the rubble, unmoving and mostly naked, is Bruce instead of the Hulk. The Hulk has taken hits before that knocked him out shortly, but never has he transformed back into Bruce this suddenly. They really need to have someone more versed in magic than Tony to look Thor and Bruce over.

First, Tony repeats his procedure with Bruce, checking for a pulse and trying to wake him. He is not actually relieved to find Bruce in the same condition as Thor.

The air is filled with an almost palpable tension, like when Thor is furious, causing storm clouds to gather around the tower. Tony hopes that means Thor is regaining consciousness.

“They’re unconscious but according to JARVIS not in immediate danger,” Tony informs the rest of the team over the comms. “We need to wrap this up quickly.”

And, surprisingly, they do. It is almost as if the wizard has lost all interest in the fight once he managed to take out two of the Avenger with his big ball of light. He laughs and taunts them, but does not create any more guardians for himself, and when Clint and Tony double their efforts to take him down, he vanishes with a twirl of his cloak. The way he is cackling makes Tony believe that this is not the last they have seen of him.

For now, though, they have more important concerns. They need to get their teammates home and make sure they are all right.

* * *

Thor wakes up screaming. Something is terribly wrong with him. His skin feels like it belongs to someone else, like something is scratching at it from the inside. His mind, too, is so full all of a sudden that he can barely grasp a single thought.

He hears voices talking over each other, some of them familiar, but some seem to come from inside his head.

Before he has a chance to collect himself, his world erupts into green.

* * *

Bruce comes to in a hospital room. That in itself is such a familiar sight that he merely sighs long-sufferingly, wishing the Hulk would not control his life to such an amount that, even when he is withdrawing into Bruce’s skin, it leaves him exhausted to the point of passing out.

When he sits up, intent on getting back to his room to get some real sleep, he notices he is not connected to the heart monitor. Not even an IV line is sticking out of his arm. No matter how often he told the doctors here that all of that is unnecessary – ignoring the fact of the Hulk’s sheer existence, nothing is actually wrong with him that means he needs to be supervised – they always insist on the whole shebang.

It is strange that they would have refrained from doing so all of a sudden. He tries to think back to what happened, but all he remembers is the Avengers alarm going off and then just flashes and a sudden, blinding light. Then nothing.

Frowning, Bruce makes to get out of bed when he notices that the metal railing, even left down as they are, are wrapped with blankets. That, frankly, does not make any sense at all. Even if he was thrashing around, which sometimes happens after a transformation, he was in no danger of hurting himself with them.

A sudden noise has him looking up. Tony stands in the doorway, untypically reserved. Normally, he would have already come in and jumped onto Bruce’s bed, chattering either about the fight or some experiment he is working on. Tony Stark does not just hold back.

“How are you feeling?”

Bruce’s frown deepens. That, too, is strange. Tony cares a lot about all of them, but he is usually not this direct about it. The question has enough weight to it to really make him think about it, too.

“Calm.”

The moment Bruce says that, he realizes it is true. A stillness has taken hold of his mind that he has become utterly unused to, leaving all his thoughts to echo without an instant response.

The Other Guy is a constant presence in his mind. Sometimes, after a fight, he is muted when they are both exhausted. This utter silence, however, is frightening in its intensity. Bruce never thought the absence of his constant struggle to keep the upper hand against the Hulk would trouble him this much.

“What happened?” Bruce asks, his hands clenching around the bed sheet. He is frantically searching the recesses of his mind for the Hulk’s presence – and finds nothing.

“It’s all right, Bruce,” Tony says, holding out his hands in a calming gesture. He still does not come into the room, though. “Don’t panic. It’s –”

“What. Happened.”

Thunder crashes outside, making both of them flinch. Bruce would not have paid it any mind, if there was not plain worry written all over Tony’s face as he glances out the window. The sky outside is black, roiling clouds surround the tower as if it is their epicentre. It looks close to what it does when Thor is raging.

“You need to take a deep breath,” Tony says in a deceptively calm tone, still looking at the window. “Everyone’s safe. I’d come closer but you’re only going to shock me again if I do, and I don’t think my heart would like that.”

Tony is talking nonsense. He looks frazzled and tired, making Bruce wonder whether the battle was more taxing than what he can tell from the few snippets he remembers.

“Shock you?” Bruce echoes, even though that is not his main concern by far at the moment. If someone developed a weapon or method to temporarily – or permanently – take out the Hulk, Bruce needs to know. Although he is not sure what he would do with that information, not while he is on the verge of panic at _not_ having to struggle against the Other Guy. “Tell me what’s going on.”

Sighing, Tony runs a hand through his hair, making it stick up worse than before. The rings under his eyes appear to get darker by the minute.

“You and Thor were hit by a spell,” Tony says, then falls abruptly silent. It has new worry shooting through Bruce. What if something serious happened to Thor? What if the Hulk did something to him? Before he can voice that, Tony continues, dragging each word out as if he would prefer to swallow them back down. “Now he’s very much green all the time and you have an electricity problem.”

Bruce cannot do anything but stare. He is sure he has misheard or that Tony is making a very bad joke. His face remains serious, though, even though none of this makes sense.

Looking down at his hands, Bruce notices for the first time the tingling in his fingertips. Cautiously, he reaches out for the bedrails and pulls the blanket to the side. A spark flies immediately from his index finger, travelling through the metal rail with a hum. He does it two more times, reaching the same result.

That is one hell of an _electricity problem. _Once that realization hits, Bruce is reminded of what else Tony said. He is not nearly ready to process any of what is happening right now. All he knows is that sparks are flying from his fingers and that his head and body, for the first time in years, are completely his own.

“Thor is what?” Bruce asks, deceptively calm.

Tony, to give him credit, looks right into Bruce’s eyes. “Thor is battling the Hulk.”

“As in the two of them are fighting somewhere or –” He trails off. None of this makes sense. The Hulk is not a separate entity, not in the way that he can just jump out of Bruce’s head into the real world without taking Bruce with him. They are one. In a way, Bruce understands that now although he has always refused to believe it before.

“Or,” Tony says like that is an acceptable answer. He looks decidedly uncomfortable. “Somehow you can call lightning, and Thor is housing the Hulk in his body.”

For a moment, everything is still. Neither of them moves, while Bruce’s mind is as empty as it has not been in forever. Then, all at once, panic hits.

“Where is he?” Bruce jumps to his feet, almost yelling. The thought of someone else having to carry the burden of the Hulk is unbearable, especially since there is no way of forgetting how much destruction Bruce wrought before he managed to get the slightest bit of control over the Hulk. “We need to sedate him. They might just tear down the whole tower and –”

“Calm down,” Tony cuts through his worried rambling. He finally takes a step into the room but comes to an abrupt halt, grimacing. There is a crackling tension in the air, Bruce notices that only now. “Thor has turned green several times in the last hour, but the only thing they’ve destroyed until now are Thor’s clothes. Their fighting is a purely internal thing. If that makes sense.”

It does not. The Hulk’s only purpose is to destroy. There is no reasoning with him, no getting the upper hand.

“Take me to them,” Bruce demands. He walks forward but stops when the air keeps crackling. He clenches his hands, hides them against his hospital gown, but it does not get much better.

“Thor has sent us all away. Roared it really,” Tony says and looks apologetic about it, almost as if he is afraid how Bruce will react to being kept away from the Hulk.

He should be rejoicing or, at the very least, be glad to be rid of the Hulk, however temporarily. He does not wish this burden on anyone else, though, much less a friend. And that is ignoring the pain and destruction they can cause.

“We need to take care of your sparkling problem first,” Tony continues when Bruce does not know what to say, what to do. “I brought you gloves.”

With automatic movements, Bruce catches the gloves out of the air when Tony throws them at him. They are surprisingly modest for something obviously coming out of Tony’s workshop. He pulls them on, not wanting to think about what they are made of or why he needs them. If he has shocked people just by them coming too close to him, it is no surprise why he was not attached to any of the monitoring devices and why no one dared to stick a needle in him.

Gathering his thoughts as best as he can, Bruce nods. “Now,” he says in a tone brooking no argument, “take me to Thor.”

Tony wants to argue. That is what he does. In the end, though, he merely shrugs and steps back to let Bruce through the door. They walk in tense silence for a few minutes directly towards Bruce’s lab and the safe room built into the back of it. Bruce is not sure he can stand the sight of someone else locked inside there.

“What’s with the storm outside?” he asks, mostly to distract himself, although he supposes the answer is not something he actually wants to hear either.

“That’s all you,” Tony says, less boisterous than he would normally have. “God of Thunder, remember. It’s been brewing since you began to wake up.”

Great, Bruce thinks, not only are they going to let the Hulk loose on New York, it is going to be during an unnatural thunderstorm too. He has seen first-hand the damage Thor can do with the lightning he calls, and Bruce would definitely prefer it if he did not accidentally burn down the whole city because he does not know how to control his new gift. Control has never really been his thing.

When they arrive in the lab, Bruce’s eyes fall immediately on Thor. He is sitting with his back against the wall, a blanket pulled over his naked form to allow him at least some privacy. His eyes are closed and his knuckles are white where he has clenched them around his knees.

Bruce’s heart immediately goes out to Thor. Nobody should have to experience that. The first transformations were the worst. Each time, Bruce thought he could fight it, could stave it off. He never could, and the more he fought, the worse it hurt.

“Thor,” he calls out without thinking, going up as close as he can. “You need to calm yourself. You need to –”

He would have rattled off all the useless advice people have given him over the years, mind tricks and mantras, none of which ever helped. In the face of his friend’s suffering, he feels helpless enough to try, though.

That is when Thor looks up, eyes falling directly on Bruce. They are gleaming green, the way Bruce has seen in the mirror far too often. Suddenly, Thor’s skin seems to ripple, and Bruce has the questionable honour of seeing someone transform into the Hulk for the first time. He feels every second, every bending of joints and stretching of muscles, as if it is happening to him, the pure agony of being ripped apart and stitched back together again wrong.

Then the Hulk is standing before him, mouth opened as if to roar. His eyes are still on Bruce, wild but strangely conscious at the same time.

“Banner,” Hulk roars and jumps forward, hands banging against the transparent wall separating them. His fists are bigger than Bruce’s head.

He truly is a monster, Bruce realizes as he takes an instinctive step back, unable to do anything more than to stare at the personification of his rage, suddenly all separate from him. This is the ugly truth of who he is.

Tony appears at Bruce’s side, hand hovering over his shoulder but never actually touching down. “Let’s get you out of here.”

Bruce wants nothing more than that. He needs to bring several walls between himself and the sight of Thor trapped inside the Hulk. “But I –” he protests anyway, although Tony thankfully cuts him off.

“Thor seems to have it under control,” Tony says, even though _control_ looks very differently from this. “But the Big Guy reacted to your presence. Let’s give them time to settle.”

When Bruce turns towards Tony, he catches a reflection of his own eyes, seeing how wild they are even without the Hulk fuelling his inner fire.

“The Hulk does not settle,” Bruce argues, desperate for them to understand that. He has tried unsuccessfully for years. “He is made to destroy.”

Tony glances between him and the Hulk, obviously put off by the fact that they are actually sharing a place but not a body at the moment.

“Well,” he says slowly, “right now, he really wants to get to you. And since we don’t know what for or what that would do to Thor, I suggest we’ll give the two of them some room.”

Bruce has some ideas what the Hulk might want with him, none of them good, but Tony is right. No matter what this situation is doing to him, he cannot do anything that threatens Thor’s well-being. Not anymore than he already has.

“I can’t –” he says and trails off, unsure what to say, what to argue against.

“Come on,” Tony smiles, his whole face gentle, “let’s make your room electricity proof.”

* * *

Nobody sees Thor for a whole week. He remains locked up in his room or the Hulk cage and refrains from commenting on how he is doing.

Meanwhile, Bruce does not know what to do with himself. Without the Hulk, he feels strangely empty, helpless even. He cannot even work or do much research concerning the nature of the spell that switched their powers, since he cannot control the electricity flowing out of his fingers.

Outside, the thunderstorm does not stop raging.

* * *

The presence of the Hulk slams back into Bruce without warning, a sudden force pushing past his superficial thoughts and settling back in his mind with so much intrusive shamelessness as if it has a right to be there.

Bruce’s instinctive reaction is relief. Disgust at himself rises only moments later, but he cannot deny that this is the first time in over a week that he does not breathe with ever-constant panic constricting his chest. That relief is not even caused by the knowledge that Thor has to be free of the Hulk now. It is just that he is complete again, no matter how often that puts him at odds with himself.

Outside, the clouds are already dissipating as the first hint of sunlight hits New York underneath. Bruce does not even have to test touching something to know that he will not shoot any more sparks from his fingers. The constant tension and slight burnt smell that has surrounded him for the past week is gone.

Without thinking, Bruce gets up, intent on finding the rest of his team to tell them the curse is lifted, that they are back to normal. A sudden thought lets him pause in the hallway, though.

Shame fills him at the mere prospect of having to see Thor. How can they remain friends after what he put Thor through? How can they even keep working together? The Hulk is Bruce’s greatest failure, his greatest shame. He cannot stand the thought of having shared it with someone. Especially not someone he admires.

“JARVIS,” Bruce says cautiously.

“Yes, Dr. Banner?” JARVIS answers immediately. Once, Bruce had felt uncomfortable at that. By now, it has become just another part of normal, another safety feature in case he turns into the Hulk where he is not supposed to be.

“Could you please tell Tony that the spell seems to be reversed?” With some hesitation, he adds, “And that I don’t want to be disturbed? I think I need some time to deal with –”

He does not know how to finish his sentence, but it appears he does not have to.

“Certainly,” JARVIS says, sounding gentle. “Don’t hesitate to ask if you need anything.”

It is not even a complete lie that he needs some rest. Living with the Hulk is a constant struggle, even though the Hulk is suspiciously quiet at the moment. It is almost like he is humming, content to be home. The week of being free has apparently robbed Bruce of all his senses. Soon enough, they will fight against each other again. They always do.

* * *

Three days later, Thor’s patience runs out. JARVIS had announced several times that Thor was on his way to Bruce’s rooms, asking about his well-being, but Bruce had sent him away each time. Avoidance is never a solution, but he really does not want to have this conversation.

Now, though, Thor stands outside of Bruce’s room, having knocked and called for several minutes, showing no inclination of allowing himself to be ignored again.

“Bruce,” he says again, tone soft despite the booming of his voice. “I will not have you hide in your room.”

The alternative is to let Bruce, and therefore the Hulk, walk amongst them again. Surely, as someone who experienced the raw rage of the Hulk himself, Thor does not want that but is too kind to say it.

Taking a deep breath, Bruce decides to get this over and done with. He opens the door but finds himself speechless. This is definitely Thor standing in front of him, tall and magnificent, hardly changed, but Bruce cannot help but remember how it looked when he was torn apart to give room for the Hulk. The shame pooling inside his stomach is getting unbearable.

“You don’t –” he says, then tries again, “I’d understand if you want to stay away from me now.”

That is not what he wanted to say. He wanted to offer to leave to make it easier on all of them. Before he can correct himself, he is rendered speechless again by the sheer confusion on Thor’s face.

“Why would I want to do that?”

He sounds honest, and still Bruce cannot contain the startled and mostly bitter laugh falling from his lips. “You know what I am,” he says slowly, full of loathing. “You’ve felt the Hulk. You –”

“Know how strong you really are,” Thor interrupts him, no trace of doubt in his voice. “To live like this, with yourself split in two, I admire you. Fearing you would be an insult to both you and the Hulk.”

The thing is, Thor sounds honest. There is no mocking or scorn hidden anywhere in his tone or face. In a way, that makes it much harder for Bruce to believe him. He could have taken yelling or an outright fight. He could have packed his things and left like he has done a thousand times before. Instead, here he is, faced with an honesty he does not know what to do with.

“I’m a monster,” Bruce says, toneless but utterly convinced this will be it.

Thor frowns as if Bruce has displeased him. When he speaks, though, it is still not at all what Bruce expects.

“You are a man sharing a body with an honourable ally.” A smile tugs at Thor’s lips that looks almost fond, enthused with excitement. “The Hulk is not to be feared. He is –”

“You fought him,” Bruce cuts in, incredulous and certain he is missing something important here. “For an entire week, you were at war with that piece of me you got stuck with. So how can you pretend the Hulk is anything but to be despised?”

It is a miracle that nothing happened during this week, that Thor managed to contain the Hulk. Thor is much stronger than Bruce, of course, which is only partly due to him being a god. Still, it must have taken effort.

“He fought me,” Thor agrees with misplaced cheer, “because he woke up to find you gone.” He looks at Bruce for a long moment as if to make sure that he understood the words. “The two of you are tethered together. You are his safe haven. He naturally struggled against me. He –” Thor shrugs with a smile. “He called me a traitor for separating the two of you.”

No matter the conviction in Thor’s tone, Bruce cannot believe him. It is kind of Thor to try to make Bruce feel better about this, but Bruce has been fighting this for years. He created this demon sitting under his skin, constantly waiting for him to show some weakness.

“I’m sorry,” Bruce offers, unsure what else to say, how to make Thor realize that he is wrong.

“Don’t be,” Thor replies brightly. “We came to an understanding.”

With undisguised bitterness, Bruce mutters, “The Hulk doesn’t understand anything.” He truly is a creature beyond reason.

Shaking his head, Thor reaches out and puts his hand on Bruce’s shoulder, not withdrawing when Bruce instinctively flinches.

“He knows fear and love,” Thor says earnestly. “That in itself makes him relatable enough.”

Bruce wishes he had never opened the door. “I don’t – I’m sorry you were burdened with this.”

“Don’t be sorry,” Thor counters immediately. He is still standing in the open door, full of patience. “It led me to see many a thing I was blind to before, even though it was right in front of my eyes.”

His gaze is warm and heavy as it rests on Bruce, speaking of things Bruce cannot quite decipher.

“What do you mean?” he asks despite knowing better. Some questions are better off unanswered.

“When I call, the storm comes,” Thor answers without explaining anything, “you calmed it.”

Just when Bruce was sure they were getting somewhere, Thor has to say something like this. A smile tugs at his lips that tastes purely bitter on his tongue. “You might have missed this, considering you were busy fighting the Hulk, but the sky has been rumbling for this entire week.”

Thor nods as if Bruce has made a good point and one that is not at all contrary to his own argument. “My storms are meant to bring about the end of armies. Yet the city still stands.” He squeezes his hand around Bruce’s shoulder before taking it back. “The storm has not wrought the chaos the thunder promised.”

“What are you saying?”

Bruce’s confusion only rises. He just does not know what is happening. Only a few minutes ago, he was ready to leave the Avengers, certain that they are better off without him. Now, though, he thinks Thor is trying to tell him otherwise.

“You are worthy of songs being sung for millennia to come. Perhaps I will write a few of my own,” Thor declares with the air of promise. His lips turn up in a crooked smile as he amends, “If you are willing to hear them.”

The friendship between them is apparently not over as Bruce had feared. On the contrary, Thor looks at him with a warmth that has not been there before, inviting and certain in a way Bruce has never been about anything.

“Don’t make your decision right now,” Thor says before Bruce can reply – which is a good thing because he is not sure what is required of him here. “Listen to what your guardian has to say. I will await your answer.”

With that, Thor turns around, a spring in his step that Bruce has not seen before. He is still not entirely sure what happened, but begins to believe that it was not a bad thing.

What he notices too is the slight crackling of the air that disappears with Thor. It has become familiar to Bruce over the past week, the constant presence of energy waiting to be released. He misses it.

When he walks back into his room, he listens into himself, half expecting the Other Guy to rage at how close Bruce let Thor come to him. Instead, he is humming almost in approval.

Nothing makes sense, that is the only thing Bruce is certain about at the moment. What he feels, too, is the wish to hear the kind of song Thor would sing about him. He just has to work on being worthy of it – and maybe accept that Thor thinks he already it. 

**Author's Note:**

> Thank you for reading.


End file.
